Electrical-wiring knob.



H. W. LAWRENCE.

ELECTRICAL WIRING KNQB, APPLICATION FILED J'UM: 10,1908.

Patented Dec. 22, 1908.

1 5 QoMah ur-rrrn same Parana Fries.

HARRY WALLACE LAWRENCE, OF DENVER, COLORADO.

ELECTRICAL-WIRING KNOB. w

Specification of Letters Patent.

Patented Dec. 22, 1908.

Application filed June 10, 1908. Serial No. 4=3 l,6962

T all whom it may concern:

Be it known that I, HARRY WALLACE LAW- 'nnxon, a citizen of the UnitedStates of Amer- And third, to provide a simple, strong, combinedelectric wire clamping and fastening knob, that is adapted to be.secured to ob-,

jects by a clamping screw extending through its axial center.

I attain these objects by the mechanism illustrated in the accompanyingdrawings, in

which:

Figure 1, is a front elevation of the improved electric wiring knob.Fig. 2,'is a side elevation of the same. Fig. 3, is a vertical,

' sectional view on the line 33 of Fig. 2.

Fig. 4, is a vertical sectional view on the line 44 of Fig. 1. Fig. 5,is a plan view of the base of the knob. Fig. 6, is a plan view of theunder side of the cap. And Fig. 7, is a plan view of the device, showingthe manner of securing the wire around the terminating knob, andwrapping it upon itself.

Similar letters of reference refer to similar parts throughout theseveral views.

Referring to the drawings, the numeral 1, designates the base portion ofmy knob. This base portion comprises a short stem portion of anysuitable non-conductive material, preferably porcelain. I preferablymake my improved knob round in shape, although it may be made of anyother form or shape. The bottom of this base portion, is flat, and

f is preferably provided with a recess 2, at its center, in order thatthe remaining ring portion will bear squarely against the wood or othermaterial to which it is secured.

Through the axial center of the length of this,

base portion, a clamping screw -'receiving aperture 3 is formed, throughwhich a clamping screw 4. extends loosely. T his base pertion is throughc axial center of whicnan apertrue 6 is formed, through which theclamp.-

pfiovided with a cap portion 5, t,

end of the base portion of my knob is provided with a raised easeportion 7, of smaller diameter than the base, diametrically through thecenter of which extends a recess 7 which is preferably of V-shape, andthe cap is provided with a depending base por tion 8, of smallerdiameter than the cap, which is provided with a depending V- shaped lug8' that fits into the recess 7 in the top of the base'portion, and thuscenters thecap on the to of the base, and at the same time prevents t ecap from turning on the.

base when the clamping screw is tightened against the cap, when screwingthe screw into wood to secure the knob into wire supporting position. Onone side of the base, and also on the same side of the cap, I formprojecting lug portions Qand lOrespectively, which are arranged toregister op ositeto one 'another and are arranged re ative to eachotherso as to stand a sllght'distance apart, and in the opposing surfaces ofeach projecting lug I form recesses 11 and 11',

preferably curvedrecesses, the surfaces of which are formed into aplurality of teeth 12, which are preferably arranged atan angle to thelength of the recess, and theteeth of the recess of the cap arereferably arranged at an opposite ang e to t e angular direction of theteeth of therecess in the base, as these teeth are not so apt-to cutinto the insulation of the wires and weaken them when the wire isclamped tight in the aperture-formed by these. recesses through the baseand cap, when the cap is clamped tight against its base by the clampingscrew. A wire securing groove 13 is also fprmedaround the base and cap,and partially between the base and the cap, and in circumferentialalinement with the wire receiving and clamping recesses. The top of thecap is preferably countersunk deep enough to permit the head of thescrew to extend below the surface of the cap.

The operation of my improved wire SUE-1 porting and tyingknob isasfollowsz' T e cap is placed on the base, and the base is placedagainst the wood or other screw receiving material to which, the knob isto be secured. The clamping screw 4 is then insorted through the cap andbase, and is screwed into the wood or other material to hold the baseportion fixed to the wood, but to leave the cap with enough movement onthescrew away from the base to insert a wire into and extend it throughthe toothed aperit is lrawn tigl t. from. its fastened end, and

then the screw is screwed into the wood until the'hoad of the screwengages the cap and forces it down onto the base, causing its;

toothed recess 11" to se a e and clam the" Wire rigidly in the tOOLHQtfrecess 11 of the base, with pressure enough to cause the teeth of theserecesses to sink into the insulating covering of the wire, and thusrigidly secure the wire against any slipping moven1ent through the knob.The knobs are thus attached at intervals to the walls, ceilings, andcasings of rooms and other portions of buildings and other thingswherever electric wires are to be run, and wherever a wire terminal is,a knob is placed and the end portion of the wire is clamped in the knoband its end is run around the circumferential groove of the knob untilit meets the clamped portion of the wire, around which it twisted, andis thus secured. The wire isthus secured to non-conductive insulatingknobs, to which it is ri idly secured against any possibility of accirenta'l displacement.

Having described my invention, what I claim as new and desire to secureby Letters Patent, is:

1. A non-conductive electric wire supporting knob, comprising a base, acap fitting on said base, a screw aperture through said cap and base, ascrew extending loosely through and-beyond said cap and base and adaptedto secure said base to wood or other screw penetrating articles, and toclamp said cap to said base, a projection on. one side of said cap and asimilar projection on the side of said base registering opposite theprojection of said cap, a recess in the face of each projection beyondthe body of said knob registering opposite'each other and adapted toform a wire receiving and wire clam mg and gripping recess laterally toone si e of the body of said knob, a plurality of singularly arrangedwire grippin teeth in the recess of the projection of said ass and aplurality pf teeth in the recess of the projection of said cap arrangedat an opposite angle to the teeth of the recess of the projection ofsaid base, and a wire receiving groove extending from said recessescircumferentially around the body of said knob at the registering edgesof said cap and base.

2. An insulating electric wiring knob, comprising a base portion and acap portion, each of which is provided with an axial aperture extendingthrough it in alinement with the other apertures, means including a doendin oblon lu ortion on said ca and D D b a recess in said base,arranged to prevent rotative inovonnn'it of said cap on said base,laterally pro ecting rug portions on said cap and base registeringopposite each other and projecting beyond the body of said knob, a

toothed aperture formed partially in the lateral projection of said capand partially in the projecting lug of said base, said toothed aperture,being positioned outside of the body of said knob and arranged topartially surround a wire, and an annular groove formed partially in themeeting edges of said cap'and base extending around said knob from oneend of said toothed aperture in said lateral lug portions to itsopposite end.

3. An insulating non-conductive knob for supporting electric wires,coi'i'iprising the base containing an annular bearing ring at itssupporting end, a diametrically arranged recess in its wire supportingend, a projecting lug portion on one side of said base portionsubstantially level with its top portion, provided with a curved wirereceiving re ess adapted to receive a' predetermined size t electricwire, said curved recess being pro-- vided with angularly arrz'ingedwire gripping teeth, a groove extending around the top edge of saidbase, and a screw receivingapen ture extending through the axial centerof said base, with a cap p ovided with. a depending lug fitting thegroove in said base and adapted to prevent said cap from turning on saidbase, a laterally projecting lug portion on one side of said capregistering opposite to the lug on said base, provided with a toothedrecess that ispositioned be yond the body portion of said cap and thatis arranged to register with said toothed wire holding recess of saidbase, a groove extending around the edge of said cap from one end ofsaid toothed recess to'its opposite end, and arrangedito registeropposite to the groove in the top edge of said base, saidcircumferential groove around said cap and 1 g oase being a continuationof the toothed groove in the PIQJBOUIIg lug portions of said cap andbase,

a clamping screw receiving aperture through

